body {
  font-family: Arial, sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  background: #000;
  overflow: hidden;
  color: white;
}

.container {
  text-align: center;
  padding: 20px;
  max-width: 400px;
  width: 100%;
  background: #111;
  border-radius: 12px;
  box-shadow: 0 0 20px rgba(255,255,255,0.08);
  transition: all 0.6s ease;
  color: white;
}

.container * { transition: all 0.5s ease; }

.container.fullscreen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  border-radius: 0;
  padding-top: 10vh;
  padding-left: 5vw;
  transform: none;
  background: radial-gradient(circle at center, #222, #000);
  box-shadow: none;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

#display {
  font-size: 3rem;
  margin: 20px 0;
  font-weight: bold;
  transition: font-size 0.6s ease, color 0.3s ease, opacity 0.3s ease;
  outline: none;
  cursor: text;
  text-align: center;
  user-select: text;
  min-width: 12ch;
}

.container.fullscreen #display {
  font-size: 18vw;
  text-align: left;
}

.buttons {
  margin-top: 20px;
  display: flex;
  justify-content: center;
  gap: 40px;
}

.symbol-btn {
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  font-size: 3rem;
  cursor: pointer;
  user-select: none;
  transition: transform 0.1s ease, color 0.2s ease, text-shadow 0.2s ease;
}

.container.fullscreen .symbol-btn { font-size: 4rem; }
.symbol-btn:active { transform: scale(0.85); }

#start { color: #4caf50; }
#pause { color: #ffd700; }
#reset { color: #e53935; }
.symbol-btn:hover { text-shadow: 0 0 12px currentColor; }

.preset-buttons { margin: 10px 0; display: flex; justify-content: center; gap: 10px; }
.preset-btn { padding: 6px 12px; border-radius: 6px; border: none; cursor: pointer; background: #333; color: white; transition: background 0.3s ease; }
.preset-btn:hover { background: #555; }

/* Time input boxes */
.time-inputs-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 5px;
  margin-bottom: 20px;
}

.time-inputs-wrapper input {
  width: 60px;
  padding: 8px 10px;
  font-size: 1.2rem;
  text-align: center;
  border: 2px solid #4caf50;
  border-radius: 6px;
  background: #111;
  color: white;
  transition: border 0.3s ease, background 0.3s ease;
}

.time-inputs-wrapper input:focus {
  border-color: #ffd700;
  background: #222;
  outline: none;
}

.time-inputs-wrapper span {
  font-size: 1.2rem;
  color: #fff;
}

/* Hide inputs in fullscreen */
.container.fullscreen .time-inputs-wrapper {
  display: none;
}